Packaging of ferrous metal objects



y 3,1955 M. J. SHNITZLER ETAL PACKAGING OF FERROUS METAL OBJECTS Filed July 19. 1950 Fig.

INVENTOR6 I BY i I ZATTOR/VEV United States Patent 0" 2,707,551 PACKAGING or FERROUS METAL OBJECTS Meyer J. Shnitzler, Brookline, Thomas P. Norton, Watertown, and Stanley G. Kindred, Newtonville, Mass, assignors to The Gillette Company, a corporation of Delaware Application July 19, 1950, Serial No. 174,664

3 Claims. (Cl. 206-16) This invention relates to improvements in the packelfective as to temperate climates if unusual conditions ii are not encountered, but affords inadequate protection in tropical countries, where conditions of high temperature and high relative humidity prevail, the corrosion being most pronounced if the blades are stored, as is most usual, in the acidic atmosphere of a typical home medicine cabinet. When the blades are not individually wrapped, as is true, for instance, in the case of the dispenser type packages currently in vogue, the protection provided by anti-rust oils as presently compounded is iIlSllfi'lClBl'lt even for temperate dimes-here, again, espe cially where the blades are exposed to the atmosphere of a home medicine cabinet.

In accordance with the present invention, we dispense with the oil film entirely or we supplement its action by the incorporation in the package of a small amount of a compound which, in the presence of acidic fumes, as those encountered in the environment of a typical home medicine cabinet, converts to an acid capable of reacting with the raw metal surfaces of the blades, whether oiled or not, to provide thereon a rust-preventing coating. Our invention thus involves the utilization of the very substances normally promoting corrosion of blades in home medicine cabinets in the avoidance of such corrosion.

The compound which we prefer for incorporation in the package is sodium benzoate, which converts to benzoic acid. The conversion may be brought about, for example, by acetic or citric acids, both commonly found in hair rinses for instance; mono-di or tri-chloracetic acids, present in Wart and mole removers; formic acid, used in preparations employed in the treatment of neuralgia and rheumatic afllictions; oxalic acid, a common ingredient of prescriptions for bronchitis and asthma; picric acid, used in antiseptics; sulfanilic acid, employed as an analgesic and in the treatment of laryngitis; tartaric acid, found in effervescent powders; Valerie acid, present in sedatives, etc.

Apart from acids contained or derived from medicinals, cosmetics, and the like, the conversion of the sodium benzoate to benzoic acid may result from reaction of the benzoate with acid fumes derived through oxidation of evaporated paint solvent or of linseed oil, a common component of paints employed in the painting of bath rooms.

We are aware that sodium benzoate has been previously recognized as a corrosion inhibitor, but always heretofore it has been employed in actual contact with the metal surfaces desired to be protected. In a package For '1.

package.

as the carrier for the compound or, alternatively, a second 2,707,55l Patented May 3, 1355 ice conforming to the invention the contained blades or other articles, or at least the bulk of them, stand in spaced relation to the sodium benzoate or other compound, actual contact being unnecessary since the acid providing the protective film acts in vapor phase-a critical feature of the invention.

The dispenser type packages, previously referred to, usually include a so-called reminder tab which comes into full view on the removal of the last blade from the This tab may, with advantage, be employed tab or insert may be used. If the dispenser is made wholly or in part of plastic, the compound may be incorporated in the plastic. Metal dispensers or dispensers including metallic parts may incorporate the compound in the lacquer or enamel applied over the metal surfaces.

The amount of the inhibitor compound incorporated in the package varies with the identity of the compound, the size of the package and other factors, including the climatic conditions to be encountered. The package may contain from 0.05 to 0.25 gram of the compound where sodium benzoate and a conventional razor blade package are used.

In order to insure against rusting of the blades during the period intervening their shipment from the factory and the time they reach the ultimate customer and, in any case, Where the most positive protection is required or considered desirable, we may include an acid adapted to bring about conversion of the compound in the package itself. Ordinarily, the activating acid is employed in an amount substantially less than would be required to convert all of the compound to active acid, since once the package is placed in a medicine cabinet or similar environment any incorporated activating acid still remaining is normally superfluous. It is, of course, within the scope of our invention to supply the activating acid through a compound thereof which releases the acid in proper amounts.

The activating acid should not be unduly corrosive of itself. The amount thereof included in the package where it is reasonable to assume the package will ultimately reach a home medicine cabinet is determined by rough estimates as to the length of time the package will be in transit and in storage with the distributor and the length of time it will be on the dealers shelf before it is sold. Ordinarily, the amount of activating acid is equivalent to the amount required to convert from 25 to 75% of the inhibitor compound to active acid.

Assuming, for purposes of illustration, that the inhibitor compound is sodium benzoate, as preferred, and assuming further that the sodium benzoate is incorporated in the package to the extent of 0.1 gram, conversion of one-half to benzoic acid can be effected by inclusion of about 0.021 gram of acetic acid:

0.1 gm. sodium benzoate-0.0007 mol. 60 (mol. Wt. of acetic acid) 0.00035 (Hi required for 50% conversion)=0.02l gm.

The amounts of other acids necessary to achieve the 50% conversion or a higher or lower conversion can be readily calculated in a similar manner by those skilled in the art.

In lieu of the practice above described, we may insure against interim rusting by treating the blades at the factory with active acid or we may actually include active acid in the package rather than an acid which acts to release active acid through its effect on the inhibitor compound. When the latter practice is followed, the amount of inhibitor compound may be reduced approximately proportionately to the amount of active acid used. Thus, when We incorporate benzoic acid in one of the conventional packages with sodium benzoate, the ben- Q: zoic acid and benzoate may be present in amounts within the ranges 0.005 to 0.1 gram and 0.025 to 0.125 gram, respectively.

Ir" the blades are treated at the factory with active acid, we prefer the process described in copending application, Serial No. 174,662 filed July 19, 1950, now Patent No. 2,674,553, in accordance with which benzoic acid vapors, for example, are passed into contact with the blades in company with water vapor. Such procedure of itself, in the absence of any sodium benzoate in the package, provides excellent protection, but the protection does not compare with the continuing protection afforded when the treated blades are packaged in accord" ance with the present invention. Just as in the case of the packages incorporating active acid, the packages in which the blades have been factory-treated generally contain a reduced amount of the inhibitor compound.

Any active or activating acid incorporated in the package may be carried on an insert (which may or may not be the insert carrying the inhibitor compound) or it may be contained in the material of the carton or other container, in the carton wrapper or the adhesive used in its application, or in any other suitable place, all as indicated hcreinoe forc. Additionally, the active or activating acid may be incorporated in the lacquer and/or oil with which the blades may be coated.

Carrier tabs or inserts employed according to the invention are usually of fibrous composition, as paper. The insert (or the sheet from which it is cut) is ordinarily impregnated by saturating it with a solution of the chemical and drying. In general, an aqueous solution is used if the chemical is sufficiently water soluble. Where the chemical is incorporated in a plastic, it generally may be added to the plastic material before molding. The chemical may or may not be soluble in the plastic material.

Preferred embodiments of our invention are illustarted by the accompanying drawings in which:

Fig. 1 is a plan of a dispenser type razor blade package;

Fig. 2 is an enlarged section on the line 2-2 of Fig. 1;

Fig. 3 is a plan of an insert suitable for use in the dispenser, this figure being drawn, as Fig. l, to actual scale.

Since the illustrated dispenser It) is fully described in copending application Serial No. 37,723, filed July 8, 1948, now Patent No. 2,664,999 issued Jan. 5, 1954, a detailed description of the mechanical features of the same herein is not considered necessary. However, it should be pointed out that the casing of the particular dispenser is formed entirely of plastic, being constituted of two parts 12 and 14 fastened together by snap action, Blades 16, which are unwrapped, are superposed in an offset or staggered pattern over a bifurcated bow spring 18 which straddles the posts 20, integral with the bottom plate 14 and centrally positioned with relation to the width theerof. These posts are shaped to be received in the slots 22, which adapt the blades for reception in the particular safety razors for which they are designed. As shown, each post extends through three blades, the post occupying substantially less than half the length of the slots.

Projections 24, spaced as indicated in Fig. 2 around the thumb-opening 26, extend to a point below the level of the upper surfaces of the posts. Spring 18 constantly urges the blades against these projections. in the assembling of the dispenser, the spring is inserted through the slot 28 after the dispenser has been loaded with the blades and the upper or cover plate 12 applied. The outer edge of the closed end of the spring, which is of elongated U-shape, engages with a shoulder 3t? in the lower plate 14, the shoulder operating to retain the spring within the casing.

To discharge a blade from the dispenser, the thumb is inserted through the opening 26 and pressed against the surface of the uppermost blade to move the same in the direction indicated by the arrow indicia on the blade. The blades ringing the left hand post 20 are discharged through the slot 34, those ringing the right hand post through the slot 36. Guide rib 32 deflects the leading edge of the blade toward the discharge slot and is then received in the slot 22 in the blade.

In accordance with the present invention, as preferably applied to such a dispenser, We provide a cardboard tab 39, as shown in Fig. 3, which is impregnated with the inhibitor compound, most suitably sodium benzoate. The tab may also be impregnated with an active or an activating acid, as previously described, or the acid may be incorporated in the body of the plastic casing. Alternatively, the tab may be employed only as a carrier for the acid, the inhibitor compound rather than the acid being incorporated in the plastic. The tab is slotted at til so that it can be ringed around the posts 20, and is normally positioned in the dispenser, as shown, between the spring 18 and the lowermost blade. Notches 42 are used as guideways in the insertion of the tab by mechanical means which need not be described here.

it is not to be taken from the foregoing that our invention is limited to the packages specifically described, for it is generally applicable to the housing of ferrous metal objects. As to objects other than razor blades, it is nearly always necessary to include an activating acid in the package and, as a rule, in an amount capable of gradually converting all of the inhibitor compound to active acid.

Among compounds which may be used in place of sodium benzoate in the practice of the invention may be mentioned sodium salicylate and sodium phthalate and their alkylatcd congeners. These salts, which yield salicyclic acid and phthalic acid respectively, are not to be considered as exact equivalents of sodium benzoate in relation to razor blade packages, because they require for their activation stronger acids not always found in a home medicine chest. However, they may be employed with substantially equaladvantage if an activating acid is included in the package. Diand trich'loroacetic acids, oxalic acid, and picric acid are exemplary of acids capable of effecting the conversion in either case.

We claim:

1. In a razor blade dispensing magazine having an exit opening therein, a plurality of stacked steel razor blades housed in said magazine, each blade having at least one sharpened edge, and means for maintaining said blades with their sharpened edges out of contact with said magazinc and in position for successive individual ejection from the magazine through said exit opening, the improvement which comprises in combination with the foregoing, a supply of a non-volatile compound selected from the class consisting .of sodium benzoate, sodium salicylate, and sodium phthalate, said non-volatile compound being in said magazine in-spaced relation to and out of physical contact with the sharpened edges of said blades and being present in a suhicient amount to be converted to its respective volatile acid on meeting environmental acidic vapors thereby to automatically release said volatile acid to react with the blades to form a rust-inhibiting protective film thereon.

2. in a razor blade dispensing magazine having an exit opening therein, a plurality of stacked steel razor blades housed in said magazine, each blade having at least-one sharpened edge, and means for maintaining said blades with their sharpened edges out of contact with said magazine and in position for successive individual ejection from the magazine through said exit opening, the improvement which comprises in combination with the foregoing, a supply of non-volatile sodium benzoate, said non-volatile sodium benzoate being in said magazine in spaced relation to and out of physical contact with the sharpened edges or" said blades and being present in a sufiicient amount to be converted to volatile benzoic acid on meeting environmental acidic vapors thereby to autoaroma 5 6 niatically release said volatile benzoic acid to react with 2,324,016 Nadeau et a1. July 13, 1943 the blades to form a rust-inhibiting protective film there- 2,504,200 Johansson Apr. 18, 1950 on. 2,534,201 Hutter Dec. 12, 1950 3. The razor blade dispensing magazine as set forth in claim 2 further characterized in that said supply of 5 F PATENTS non-volatile sodium benzoate is impregnated in a fibrous 596,160 Great i f 30, 1947 insert, and said impregnated insert is positioned between 600,323 Great Bl'ltam P 1943 the loyvermost blade of the stack and the bottom of the OTHER REFERENCES magazme' 10 W. H. I. Vernon: Corrosion Control in Journal of References Cited in the file of this patent the socilety'of Chemical Industry, vol. 66, May 1947, pp.

138 to 42.v UNITED STATES PATENTS U. S. Dispensatory, 24th ed., 1947, p. 1057, Sodium 2,007,046 Friedman July 2, 1935 Benmate- 2,274,058 Goebel et a1. Feb. 24, 1942 15 

1. IN A RAZOR BLADE DISPENSING MAGAZINE HAVING AN EXIT OPENING THEREIN, A PLURALITY OF STACKED STEEL RAZOR BLADES HOUSED IN SAID MAGAZINE, EACH BLADE HAVING AT LEAST ONE SHARPENED EDGE, AND MEANS FOR MAINTAINING SAID BLADES WITH THEIR SHARPENED EDGES OUT OF CONTACT WITH SAID MAGAZINE AND IN POSITION FOR SUCCESSIVE INDIVIDUAL EJECTION FROM THE MAGAZINE THROUGH SAID EXIT OPENING, THE IMPROVEMENT WHICH COMPRISES IN COMBINATION WITH THE FOREGOING, A SUPPLY OF NON-VOLATILE COMPOUND SELECTED FROM THE CLASS CONSISTING OF SODIUM BENZOATE, SODIUM SALICYLATE, AND SODIUM PHTHALATE, SAID NON-VOLATILE COMPOUND BEING IN SAID MAGAZINE IN SPACED RELATION TO AND OUT OF PHYSICAL CONTACT WITH THE SHARPENED EDGES OF SAID BLADES AND BEING PRESENT IN A SUFFICIENT AMOUNT TO BE CONVERTED TO ITS RESPECTIVE VOLATILE ACID ON MEETING ENVIRONMENTAL ACIDIC VAPORS THEREBY TO AUTOMATICALLY RELEASE SAID VOLATILE ACID TO REACT WITH THE BLADES TO FORM A RUST-INHIBITING PROTECTIVE FILM THEREON. 